Instead of four pairs of :1 :15 bit fields, use an array of four :1,
:15 structs. This allows to replace the case folding traits classes
with a simple enum that indexes into said array.
I don't know what the WASM #ifdef'ed code is supposed to effect (a :0
bit-field is only useful to separate adjacent bit-field into separate
memory locations for multi-threading), but I thought it safer to leave
it in, and that means the array must be a 64-bit block of its own, so
I had to move two fields around.
Saves ~4.5KiB in text size on optimized GCC 10 LTO Linux AMD64 builds.
Change-Id: Ib52cd7706342d5227b50b57545d073829c45da9a
Reviewed-by: Lars Knoll <lars.knoll@qt.io>